The research is to study the enzymatic and nonenzymatic reactions of glyoxylate, a highly reactive aldehyde. The enzymatic work is concerned mainly with reduction and oxidation of glyoxylate to glycolate and oxalate, respectively. These reactions are catalyzed in mammalian systems by lactate dehydrogenases, utilizing diphosphopyridine nucleotide as the coenzyme. In related work the biological catabolism of the anesthetic methoxyflurane is investigated since oxaluria is a common finding after anesthesia with the agent. The aim is to learn whether the glyoxylate is an intermediate in the catabolism. The nonenzymatic reactions of glyoxylate under study simulate the enzymatic reactions. Glyoxylate reacts with diphosphopyridine nucleotide analogs in the presence of an amine to yield stable condensation products. The mechanism of formation and the structure of the products are currently under investigation.